visibilité

Visibilité is a French noun that denotes the quality or state of being visible. It can refer to the physical capacity to be seen, or more broadly to how noticeable or exposed something is.

In meteorology, visibilité (often called prevailing visibility) measures the greatest distance at which a person can distinguish a standard object from the horizon under current conditions. Readings are reported in meters or kilometers and are critical for aviation, maritime navigation, and road safety. Fog, rain, snow, dust, or smoke reduce visibility. Measurements may be taken by instruments such as transmissometers or forward-scatter meters, or by human observers. Variable visibility can affect planning, operations, and emergency response.

In optics and astronomy, visibility describes the contrast between a target and its background and influences perceived sharpness and detail. It depends on illumination, background brightness, atmospheric scattering, and the resolving power of the observing instrument. In photography and cinematography, visibility relates to how clearly scenes or subjects are rendered given exposure, lighting, and processing.

In computing, visibility denotes the scope of access to identifiers or resources. Programming languages implement visibility modifiers (such as public, private, or protected) to restrict or permit access in modules, classes, or components, affecting encapsulation, maintainability, and refactoring.

In marketing and media, brand visibility refers to how prominently a brand, product, or message appears to the target audience. It is linked to awareness and is often measured through impressions, reach, and recall, shaping strategic decisions and budgeting.